It only took about two years for someone to finally run a realistic simulation investigating this.
Cloth masks probably have a very, very low efficacy, but when you're dealing with exponential growth like that which governs viral transmission, even small mitigations can be impactful over a long period of time.
I'm kinda worried about the environmental impact of only being able to use n95 or kn95 masks several times before they lose the electrostatic charge that makes them so effective. Everything sucks.